


Forgive Me Father For I Have Sinned

by witchofobscenity



Category: Fate/Zero, Fate/stay night & Related Fandoms
Genre: Blasphemy, Blood, Broken Bones, Choking, Consent Issues, Dubious Consent, M/M, Non-Consensual Blow Jobs, Non-Consensual Bondage, Not Safe Sane and Consensual, Now That's What I Call Blasphemy, so much blasphemy
Language: English
Status: Completed
Published: 2019-01-03
Updated: 2019-07-21
Packaged: 2019-10-03 15:29:48
Rating: Explicit
Warnings: Rape/Non-Con
Chapters: 4
Words: 8,555
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/17286668
Author URL: https://archiveofourown.org/users/witchofobscenity/pseuds/witchofobscenity
Summary: Fucking Gilgamesh was unlike anything Kirei had ever experienced before.





	1. In the name of the Father

**Author's Note:**

> Guess who's back on their bullshit. It's me, bringing more trash fic. I started this fic like six months ago, and I'm slowly working to fix and finish it, but I figured I'd post this first part because it seemed complete to me. 
> 
> Please read the tags. I'm gonna update them as I post the fic, and there's plenty in here that might upset you. Or entice you. No judgement. I wrote this mess.

Fucking Gilgamesh was unlike anything Kirei had ever experienced before. 

 

It was nothing like fucking his wife. Some of it may have been because Gilgamesh was a man, but Kirei supposed it was mostly just because Gilgamesh was Gilgamesh. 

 

Gilgamesh was not subtle when he wanted something. He was an open book on what he found amusing and annoying. He took what he wanted and threw away what bored him. Still, Kirei felt that he didn’t understand the other man at all. 

 

The first time he fucked the Archer, it was right after he had murdered Tokiomi. The blood hadn’t even dried before he had the servant bent over a pew. 

 

Of course, that made it sound like it was somehow Kirei’s idea. It most certainly was not. He had meant to return to his quarters in the rectory, but before he could reach it, the other man had turned him around and grabbed his shirt with both hands and forced their lips together. 

 

At first, Kirei was too shocked to do anything, but as Gilgamesh continued to press into his mouth, he gained enough awareness to push the other man away. Gilgamesh stumbled backwards but smirked at him. 

 

“What?” the servant asked innocently. “Did you not enjoy that?”

 

“Archer,” Kirei warned. 

 

“Yes?” Gilgamesh slinked back towards Kirei but kept his hands to himself for the moment. 

 

“Don’t,” Kirei growled. 

 

“Why must you deny yourself things that will bring you pleasure?” Gilgamesh raised a hand to stroke the priest’s cheek but Kirei caught his wrist.  

 

“I said no, Gilgamesh,” Kirei told him, squeezing the other man’s wrist hard enough that he winced. 

 

“You know,” Gilgamesh mused, wrenching his hand out of Kirei’s grasp. “I don’t need you to say yes. I could just take what I wanted.” 

 

Kirei felt something that might have been fear. His stomach dropped and his pulse raced. It had to have been fear. What else could make him feel so alive?

 

Gilgamesh snapped and his chains appeared to wrap around Kirei’s forearms. He took advantage of the priests confusion to surge forward and kiss him again. Kirei’s mouth had fallen open in surprise and Gilgamesh forced his tongue inside his mouth. 

 

Kirei quickly gained his bearings and tried to push the Archer off of him. However, he was bound tightly and couldn’t get the leverage to make any progress. Instead he brought his knee up to crash into Gilgamesh’s groin. The servant staggered back, and Kirei used the extra space to raise his bound arms up and bring them down hard across the others mans face. 

 

Gilgamesh collapsed to his knees panting. The chains around Kirei’s arms disappeared. He used a newly freed hand to pull Gilgamesh back up by his hair. He forced their faces close. 

 

“You may be a king,” he breathed, “but I am your Master.” 

 

Gilgamesh laughed and leaned forward to bite at the priest’s neck. Kirei cried out as teeth carved into his flesh. He pulled Gilgamesh off of him and glared. Gilgamesh was smiling at him, licking the blood off of his lips. 

 

“Why do you have to push me like this?” Kirei growled. Gilgamesh just smirked at him. The priest felt rage fill his chest and tightened his grip in the other man's hair. This time when Gilgamesh leaned in to kiss him, he kissed back. 

 

Perhaps “kiss” was not the right word. Kirei was pretty sure kissing didn’t normally involve so much teeth. He pushed forward into his Servant’s mouth. Gilgamesh bit into Kirei’s lip, and Kirei cried out. Gilgamesh forced his tongue into the priest’s mouth and licked around it. Their noses mashed against each other and their teeth clacked together. 

 

Eventually Kirei pulled back, panting. There was still a line of saliva between their mouths and he could see his own blood smeared around Gilgamesh’s lips. 

 

“Are you sure you don’t want this?” Gilgamesh taunted him. Kirei tried to reply but all the he could force out was a growl. This seemed to greatly amuse the Servant. He brought one hand to Kirei’s crotch and ran a finger up the obvious bulge there. Kirei growled again. 

 

“Why don’t you just let me do this?” he asked evenly, now cupping the priest’s clothed erection with his palm. “It’s what you desire. There’s no need to hold back.” 

 

Kirei said nothing, just panted and stared intently into his servant’s eyes. He watched as Gilgamesh sank slowly to the floor. 

 

“Gilgamesh,” Kirei said, almost begging.  

 

“Yes?” Gilgamesh asked, still rubbing the front of Kirei’s pants. 

 

“I am a man of God,” Kirei reminded him. 

 

“Then how better could I serve you than on my knees?” Gilgamesh leaned forward to press a kiss to the priest’s straining erection. 

 

The Archer deftly unbuttoned and unzipped Kirei’s trousers. He slipped his hand into his underwear and pulled out the priest’s cock. 

 

Kirei swore he stopped breathing. He stared unblinkingly at his servant kneeling at his feet, long nimble fingers wrapped around his erection, mouth hovering infuriatingly close. He could feel Gilgamesh’s hot breath on his sensitive flesh. 

 

“Tell me no and I’ll stop,” Gilgamesh taunted, “tell me you don’t want this.”

 

Kirei stood trembling, hands balled into fists at his sides. He shouldn’t want this. This shouldn’t be what brought him pleasure. He could accept that he found joy in destruction; that he wanted to cause pain and suffering. Those things were inevitable in life. You could say that coming to enjoy them was even natural. This, however, was beyond that. He, a priest, was about to have sex with another man in his own church. It was perverse even for him.

 

Yet the sight of Gilgamesh on his knees, practically drooling for his cock, turned him on more than he thought possible. In the end Kirei said nothing and that was enough for Gilgamesh. He slid the man’s erection into his mouth all the way to the hilt and Kirei saw stars. 

 

“God,” the priest swore, reaching out for something to steady himself. He found Gilgamesh’s hair and laced his fingers in it. Gilgamesh hummed contentedly as he sucked up and down his cock. 

 

It was indescribable. Kirei had never had sex for pleasure before. He had bedded his wife but only for procreation purposes. Not that the experience hadn’t been nice, but this was so much better. Gilgamesh was an expert with his tongue, licking and sucking, kissing and nipping, working his way up and down until Kirei forgot about everything except Gilgamesh’s mouth. 

 

Just when Kirei thought he could take no more, Gilgamesh stopped. He pulled off of Kirei’s cock with an obscene pop and rose to his feet. 

 

He drew close to Kirei wrapping his arms around him. He forced their hips together, pressing his clothed erection into Kirei’s hip. “Why don’t we move onto something more fun,” Gilgamesh purred. 

 

Kirei suddenly felt a spike of fear. He was not a master on sex between men but he did have some idea how it worked. One of them would have to be the… receiver. He had no desire to be violated by Gilgamesh. 

 

Kirei wondered if Gilgamesh was thinking the same thing because their next kiss was even more of a power struggle. They both pushed forward, unwilling to relent for even a second. When they pulled apart for air, Gilgamesh leaned forward to whisper into his ear, “what if I fucked you right here in plain view of your God?” 

 

That flipped a switch in Kirei. He could not let that happen. He grabbed Gilgamesh tightly by the shoulders and spun him around. He forced the man down until he was bent over a pew. 

 

Frantically Kirei worked to force off Gilgamesh’s pants. He tugged and yanked until something tore and he could slide the article down to his servant’s ankles. 

 

Gilgamesh, who’d had the wind knocked out of him, raised his head and attempted to twist back around to look at his Master. Kirei expected him to try to fight back again but he just stared lustily back at him. 

 

Kirei took his achingly hard dick in his hand and lined it up with Gilgamesh’s ass. Gilgamesh opened his mouth to say something but Kirei was already forcing himself inside. 

 

“God, Kirei, fuck!” Gilgamesh cried out in pain. Sure, it was fun to fuck with no lube or no prep sometimes but with someone as big as Kirei it fucking hurt. He clawed at the wood bench in front of him, trying to remain collected. Kirei was pushing in despite resistance, paying no mind to Gilgamesh’s groans. 

 

When Kirei was fully inside, he stopped for a moment. Gilgamesh knew it was not for his own benefit, but took advantage of the brief reprieve to adjust to the intrusion. As much as it hurt, the priest felt amazing inside of him. He was stretched in ways and felt friction in places he hadn’t in some time. His dick was as hard as ever, dripping precum onto the church floor. 

 

Once Kirei had caught his breath, he pulled out of Gilgamesh and slammed back in. Gilgamesh shrieked. He felt like he was being split in half. It was exquisite. 

 

Kirei kept up an unrelenting pace. Gilgamesh felt himself stretching to the point of tearing. He knew Kirei’s dick must be smeared with his blood. Of course it didn’t really matter. He could always have Kirei heal him later but the thought excited him. He could feel a bruise beginning to form on his cheek too and his scalp stung where Kirei had pulled his hair. He was being destroyed and the thought alone almost made him cum right there. 

 

Kirei had yet to touch Gilgamesh’s dick or brush against his prostate, but the Archer was practically writhing in pain and pleasure, moaning like a common whore. Kirei felt a desire deep in his gut to make his Servant scream again. 

 

He grabbed one of Gilgamesh’s arms and twisted it around behind his back. His Servant winced as he was forced into the uncomfortable position and the noise went straight to Kirei’s dick. He forced the limb to bend further and further. Gilgamesh felt tears form in his eyes at the agony and pathetic whining noises were escaping from his throat. God, he was so close. 

 

Kirei felt frenzied as he continued to bend back Gilgamesh’s arm. Just as he was beginning to wonder if Gilgamesh would simply keep bending forever when a sickening SNAP filled the still room and Gilgamesh screamed. 

 

“Fuck!” the Servant cried as he came, hard, against the side of the pew. 

 

Gilgamesh’s screams of agony pushed Kirei over the edge as well. His thrusting grew erratic and Gilgamesh whimpered at the change in pace, the overstimulation, and his freshly broken arm. Finally Kirei stilled, filling the other man with his cum. 

 

For a moment, the two men just stood there, breathing as though they’d run a marathon. Eventually Kirei pulled himself carelessly from Gilgamesh and tucked himself back in his pants. The other man pushed himself shakily to his feet and turned around. 

 

“Was that everything you’d hoped for?” Gilgamesh asked sarcastically. He sounded surprisingly put together after having just been fucked within an inch of his life, though there was a bit of an edge to his voice. 

 

Kirei didn’t answer but surveyed the Servant in front of him. There were bruises on his face from where he’d struck him with his chained arms. There was blood on his lip and down his thighs. His arm was hanging limply, awkwardly at his side. His face was defiant but there was still a hint of pain hidden in his expression. The sight was truly beautiful. 

 

“Shall I heal you?” Kirei asked casually. He laid a hand on Gilgamesh’s shoulder and the other man flinched. 

 

“I would appreciate that,” Gilgamesh said through gritted teeth. Kirei smirked. It made sense to heal Gilgamesh in case he needed his new servant for battle. He would want him in optimal shape for fighting. But it was very tempting to just leave him here like this, in agony. 

 

Kirei let his mana flow into the Servant, watching as his injuries faded away. When he finished, Gilgamesh straightened up and returned to his normal haughty stance. It was impressive he could still give off that kind of aura covered in blood and cum with his pants around his ankles. 

 

“I can’t wait to see you become the man you were meant to be,” Gilgamesh said cryptically and smirked. Then, without another word, he vanished. 


	2. And of the Son

**Notes for the Chapter:**

> I realize that the Holy Church is not literally the Catholic Church, but that's what I know best. I'm putting all my years of Sunday School to good (bad) use. Anyway, buckle up for some BLASPHEMY.

Kirei’s life took a very different turn after that night. It was as if something deep inside him had finally been freed. All of his dark desires came flooding out. He maintained his public appearances perfectly, but behind closed doors he was becoming something even he couldn’t control. 

 

Kirei and Gilgamesh fought all the time and fucked all the time, often simultaneously. Kirei would sometimes grab Gilgamesh by the hair and bash his head against a wall and fuck him while he was too dazed to fight back. Sometimes he would wrap his hands around the Servant’s throat and squeeze until he passed out. He would force Gilgamesh onto his knees and fuck his mouth until he couldn’t breathe. He loved how the man sounded after, trying to be elegant but with his voice hoarse from having his throat fucked raw. He used Gilgamesh in any way he wanted until the other man was bloody and broken. 

 

Of course Gilgamesh fucking loved it. As much as he screamed and fought back, seeing Kirei finding his joy in destruction was beautiful. He didn’t really care what happened as long as it was interesting and Kirei was proving to be very interesting. 

 

Gilgamesh also loved to push Kirei’s boundaries. The priest clearly still had many reservations, sexually and otherwise. A lifetime's worth of religious brainwashing was not going to be undone in one night. Gilgamesh slowly found what made Kirei uncomfortable and pushed and pushed until the man snapped. 

 

One thing Gilgamesh found was the Kirei didn’t like to touch him. Sure, he could beat him, bite and scratch him, but if his hand even brushed against his servant’s dick he drew back as if he’d been burned. Of course Gilgamesh could finish himself off and sometimes he could cum untouched and that was amazing but Kirei couldn’t keep distancing himself from his actions. Gilgamesh wouldn’t let him. 

 

One evening, Gilgamesh appeared in the church where Kirei was knelt in a pew in silent prayer. 

 

“Why are you always doing that?” Gilgamesh asked, annoyed. 

 

“I’m a priest,” Kirei said quietly, not particularly wanting to discuss religion with his servant right now. “It’s part of my job.”

 

“What has your God ever done for you?” Gilgamesh asked, walking over and perching himself on the seat next to his Master. “Why worship Him?”

 

Kirei remained silent. 

 

“I’m the one who saved your pathetic soul from a life of boring mediocrity,” Gilgamesh reasoned. “If you should be worshipping anyone, it should be me.”

 

“I do worship you, Gilgamesh,” Kirei said, still not looking up. “I love you as I love God.”

 

Gilgamesh laughed. What bullshit. He couldn’t imagine Kirei loving anything. “Well as much as I appreciate your current methods of… worship,” he began. “I would appreciate a bit more subservience.”

 

Kirei narrowed his eyes. “I am your Master.”

 

“And I your God,” the Archer countered. He stood up so he towered over Kirei’s kneeling form. “And now your God demands proof of your devotion.”

 

Kirei turned to face him, still on his knees. He reached out for his servant’s hand and took it in both of his. He pressed a chaste kiss to it. 

 

Gilgamesh laughed again. “Come on, you’re more creative than that.” He pulled Kirei up and led him out of the pew. Kirei followed dubiously. 

 

When Gilgamesh reached the front of the church he hopped gracefully onto the altar. 

 

“Where better to worship a God than here?” he asked smugly, stretching out on the table. 

 

Kirei settled himself in front of the altar between the Servant’s legs. He looked vaguely amused. “And how do you suppose I worship you?”

 

He pulled Kirei close and brought his lips to his ear. 

 

“I want you to take my flesh in your mouth like you would communion.”

 

Kirei frowned and made to walk away. “No.”

 

Gilgamesh held tight to the priest’s robes. “You would do it for your previous God. Why not me?” 

 

“It’s not the same, Gilgamesh. Let me go,” he said pulling away. 

 

Gilgamesh smiled and pulled his Master even closer. “You’ll only make this harder if you fight back. You’re going to do it either way.”

 

Kirei glared at the other man. He knew Gilgamesh wasn’t bluffing. He would make Kirei do what he wanted if he had to. He would never seriously injure Kirei but he was a Servant and much stronger than him. He could make Kirei very miserable if he didn’t comply. 

 

Gilgamesh smiled as he felt the fight leave Kirei. He gently cupped his Master’s cheeks and forced his lips on his. “You can start slow,” he said with mocking kindness. 

 

Kirei didn’t respond. Instead he reached over and began to unbutton the Archer’s pants. They were fashionable and stupid and took much longer to undo than it was worth. However, for once Kirei was grateful. He had more time to prepare himself for what he was being forced to do. 

 

Kirei knew what he did with Gilgamesh was sick. Sex was meant to produce children. It was at the very least supposed to be with a woman. But he could distance himself from the act if he could just mindlessly drive into the other man. The more personal it was, the more he was filled with a lingering guilt. 

 

It wasn’t just guilt though. Right now he felt out of control. He was powerless. His hands trembled as he pulled Gilgamesh from his pants. Maybe Gilgamesh enjoyed playing the woman’s role during sex but Kirei certainly did not. At least he had no desire to try. 

 

Kirei glared up at his Servant as he stroked up and down Gilgamesh’s hardening length. Gilgamesh chuckled. 

 

“Come now, is this really so bad?” he asked. “Go on, taste it. Maybe you’ll like it.”

 

This did not entice Kirei but he bent his head down anyway and ran his tongue across the tip of Gilgamesh’s cock. It didn’t taste like much of anything. Gilgamesh smiled down at him and ran his fingers through Kirei’s hair. Kirei flinched away from the touch but ultimately stayed put. 

 

“Keep going,” Gilgamesh said with a warning to his voice. 

 

Not wanting to prolong this any more than necessary, Kirei slid Gilgamesh’s cock into his mouth. Gilgamesh made it look so easy but Kirei could barely get half of it into his mouth. He tried to push it back into his throat but immediately pulled off, gagging. Gilgamesh practically cackled. 

 

“Do you think your God can see you now, choking on my cock?” he jeered. “How his favored son has fallen.” 

 

Kirei ignored him and plunged the length in his mouth once more. He knew better than to try to take it all at once and instead focused on licking and sucking what he could fit in his mouth. It wasn’t very enjoyable for him, his jaw was beginning to ache, but Gilgamesh was certainly having a good time. 

 

“Your mouth feels so good,” he moaned. “Fuck.”

 

Kirei eventually found a rhythm. He moved up on and down the other man’s cock, covering what he couldn’t fit in his mouth with his hand. It was incredibly undignified. His mouth was stretched obscenely and drool was beginning to drip down his chin. 

 

The priest experimented with sucking and licking the tender flesh, noting what actions garnered the best reactions from Gilgamesh. Gilgamesh was getting into the performance much more than Kirei. He was gasping and panting and moaning, pulling Kirei’s hair and bucking up into his mouth. 

 

“Are you ready for your reward,” his Servant groaned, gripping Kirei’s hair tightly. Kirei wasn’t sure what he meant until he felt a disgusting hot liquid pump into his mouth. He made to pull off but Gilgamesh held his head firmly down. 

 

When Gilgamesh finally released him, Kirei ripped his head away and spat onto the ground. He felt like he might throw up. 

 

“What a shame,” Gilgamesh mused as he came down from his orgasm. “I hope you at least swallowed a little of it.” 

 

Kirei felt disgusting and violated. He couldn’t believe he had let himself be used by his own Servant. He could still taste some of the Archer’s cum on his tongue. It was humiliating. And yet… and yet he also felt exhilarated. His heart was racing and his fingertips tingled with excitement. More than anything he was incredibly turned on. He was painfully hard, dick straining against his zipper. 

 

In one fluid motion, Kirei stood up and grabbed Gilgamesh tightly by the hair. He leaned forward until their faces were inches apart. 

 

“You had your turn,” the priest growled. “Now I get mine.”

 

Gilgamesh grinned. “As long as you don’t bore me,” he purred, wrapping his legs around Kirei’s waist. 

 

Kirei narrowed his eyes and pulled the Archer’s hair even harder. Gilgamesh hissed in discomfort. 

 

“I’ve had your body,” Kirei said seriously. “If you are truly to be my new God I must also have your blood.”

 

Gilgamesh’s spent dick twitched at that. He grinned and reached out his hand to catch the knife he had just summoned from the Gate of Babylon. 

 

“It’s yours,” Gilgamesh breathed, pressing the weapon into Kirei’s free hand. “Take it.”

 

Kirei took the knife and placed the tip gently on his Servant’s chin. He slowly dragged it down his neck and chest until he reached his collar. 

 

“This is impeding my worship,” Kirei told him, tugging the article down with his knife. “Remove it.”

 

Gilgamesh slowly reached down to grasp the hem of his shirt and pull it over his head. He tossed the clothing carelessly to the side. 

 

“Good,” Kirei said in a deep voice. He ran the blade up and down the planes of Gilgamesh’s chest, not pressing hard enough to break the skin. Not yet. Eventually the knife settled on a spot in the center of his collar bone. 

 

“In nomine Patris,” Kirei murmured, pressing the knife into Gilgamesh’s flesh and drawing a few droplets of blood. “Et Filii.” He sliced down until he came to the man's navel. He removed the knife and placed it on the Servant’s left shoulder. “Et Spiritus Sancti.” He cut across the man's chest from shoulder to shoulder. “Amen,” Kirei finished, grinning at the bloody figure grimacing beneath him. 

 

He removed the knife from Gilgamesh’s now marred body and set it on the altar beside them. The priest rested a thumb on one of the angry red lines on the other man's chest. Gilgamesh flinched away from the touched which only pushed Kirei further. He pressed harder onto the wound until droplets of blood spilled out onto the porcelain skin. 

 

Kirei rolled his thumb back and forth before raising his hand to smear the crimson liquid onto Gilgamesh’s lips. Gilgamesh frowned at him. 

 

“Are you going to take all day?” the Archer asked, annoyed. 

 

“I thought you wanted me to worship you,” Kirei said, sliding his thumb into Gilgamesh’s mouth. Gilgamesh positioned the digit between his teeth but didn’t bite down. Kirei smirked and withdrew. 

 

“You asked that I take you like I take Eucharist,” he reminded Gilgamesh, grabbing the servants waistband and sliding it down his hips. “I need to pray first.” 

 

He pulled Gilgamesh’s pants completely off and slotted himself between the Servant’s legs. Kirei’s hand slid lightly from Gilgamesh’s hip to between his legs, middle finger circling his entrance. 

 

“Lord,” Kirei said in a revenant tone Gilgamesh knew better than to trust, shoving the finger roughly into his Servant. “I am not worthy to receive you.” He added another finger. “But only say the word.” A third finger. Gilgamesh bit his lip. “And I shall be healed.” He curled the digits and Gilgamesh gasped. 

 

“Enough with this nonsense,” the Archer groaned. “Just fuck me already.”

 

“Who am I to disobey my God?” Kirei said, pulling out his fingers and drawing another moan from his Servant. The priest unzipped his pants and grasped his aching cock. He pressed it against Gilgamesh’s entrance and pushed infuriatingly slowly inside. 

 

Gilgamesh threw his head back and groaned. “Yes, Father, show me your devotion.” 

 

Kirei grabbed Gilgamesh tightly by the hips as he pounded into him. Gilgamesh suddenly noticed something peeking out of Kirei’s pocket and grabbed at it. 

 

“What’s this?” the Servant asked, brandishing the item in Kirei’s face. 

 

“A rosary,” the priest grunted. 

 

“Why do you never wear it? It’s much prettier than your other cross,” Gilgamesh said evenly. For someone who would moan and whimper at the slightest touch, he could also talk very calmly while the priest fucked him. However, Kirei loved pushing him until he was so far gone that he could barely put two words together. Seeing Gilgamesh out of control was truly beautiful. 

 

“You don’t wear it,” Kirei said, not breaking his rhythm. “You only use it to pray.”

 

“What a shame,” Gilgamesh said, sliding the beads over his head. “I’m sure they’d look lovely on you.” He rested the cross on his lips, smiling. 

 

Kirei frowned and grabbed the rosary until it was pulled tightly around the other man's neck. Gilgamesh laughed. 

 

“What? Does this upset you?” he asked, slightly short of breath. “I don’t understand you Kirei Kotomine.”

 

Kirei didn’t understand it either. He was fucking another man on an altar, for God’s sake. Why did this particular perversion bother him? Why were some of his religious teachings still so deeply ingrained in him? 

 

He had murdered Tokiomi. That didn’t upset him. He had done plenty of sick, depraved things to Gilgamesh, all of which the Servant loved but Kirei would have done without his consent. Even that he could accept. 

 

Maybe he was just still angry with Gilgamesh for forcing Kirei to take him in his mouth. Maybe he didn’t have sex for procreation or even with women but he held tight to the notion that he wasn’t a total deviant. He hated that he had to get on his knees for the Archer. He hated the rush he had gotten when he felt the man moan and gasp and squirm beneath his ministrations. He hated how good it felt to please Gilgamesh. 

 

Kirei tried to put those thoughts out of his mind and instead pulled Gilgamesh closer, tightening his grip on the rosary. He brought their mouths roughly together. He could feel the Servant gasping for breath. 

 

“God, Kirei,” Gilgamesh choked when they finally broke apart. “I’m going to pass out at this rate. I thought you liked your victims fighting back in your twisted rape fantasies.” 

 

Kirei growled. Gilgamesh was putting a mirror to all the depraved parts of Kirei’s soul and instead of feeling disgusted or ashamed, Kirei felt invigorated. He sped up his already unrelenting pace and kept a careful grip on the beads around his Servant’s neck.

 

Gilgamesh was clearly struggling to breathe now. He clawed desperately at the rosary around his neck. Fuck, Kirei really would choke him to unconsciousness at this rate. He wouldn’t kill him of course, but Gilgamesh could not really enjoy their activities when he was knocked out.   

 

Kirei looked down at the Servant choking in front of him. He had complete control of Gilgamesh in that moment, and that thought made his heart race. He could pull tighter and tighter until… But he didn’t. Instead, just as Gilgamesh looked like he really would pass out, Kirei released him. 

 

Gilgamesh gasped and took in as much air as he could. The rush of oxygen brought him finally to his climax. He came hard onto his stomach.

 

Kirei grunted as he felt Gilgamesh spasm around him, but didn’t slow. He kept thrusting into him, until Gilgamesh, clearly overstimulated, started whimpering. Kirei laughed.

 

“Can’t keep up?” he chuckled. 

 

Gilgamesh’s stamina was good, but having cum twice in such a short time was pushing his limits. He had barely even caught his breath. That didn’t mean that he was done with Kirei though. The game was far from over. 

 

Gilgamesh reached up to grasp the front of Kirei’s shirt. He pulled the priest closer and breathed into his ear. 

 

“Is this what gets you off, Kirei? Having someone completely under your control? Making them do what you want? Hurt them? Make them scream? Huh,  _ Father _ ?”

 

Kirei swore and felt his pace becoming more erratic. Gilgamesh laughed.

 

“Do you like it when I call you Father? Do you like being reminded of your status? You want to be the one in control. The one people rely on. In your church, you are akin to God.”

 

Kirei hated how Gilgamesh could push his buttons. He knew what would make him furious, but also what would arouse him beyond belief. He dug his fingers into Gilgamesh’s bare hips. He wanted to tear Gilgamesh apart, to rip him to pieces. He  _ hated _ how the Servant could get under his skin.

 

“Tell me,  _ Father _ ,” Gilgamesh smirked, wrapping his legs tighter around the priest’s waist, “Are you going to cum for me?”

 

Kirei moaned and leaned forward to sink his teeth into his Servant’s shoulder, trying to stifle the noise. It took only a few more thrusts before Kirei was spilling inside Gilgamesh. 

 

Kirei took a moment to catch his breath. Gilgamesh ran his fingers through Kirei’s hair. Kirei pulled back, shaking the Servant’s hand away. Gilgamesh laughed and let his hand drop. 

 

“Are you satisfied?” Kirei asked roughly, pulling out and tucking himself back in his pants. 

 

“You never fail to entertain me,” Gilgamesh told him, smiling, before fading away.

 

Kirei sighed and began to clean up the altar. 


	3. And of the Holy Spirit

**Notes for the Chapter:**

> There's a lot less blasphemy in this chapter, but the noncon elements are much worse. Just a warning. 
> 
> Also, my knowledge of Fate outside of Zero and some of Stay Night is very limited, so I probably fucked something up. What were Kirei and Gilgamesh doing between the Holy Grail Wars? Who fucking knows. Certainly not me.

In the years after the end of the fourth holy grail war, Kirei found himself thrust back into the pretense of normality. There were no bloody battles to satisfy his need for suffering, no murders and betrayal. He could try to get by on the average, daily suffering of his congregation, but it wasn’t the same. His relationship with Gilgamesh was his only real outlet. 

 

Of course, their relationship had also changed since the war. Not that it was weaker, but they weren’t constantly in each others presence as they had been before. Kirei was often away doing business elsewhere. Gilgamesh was left behind to blend into Fuyuki. They could manage without the other, but Kirei still felt himself getting pent up whenever they spent too much time apart. 

 

One of the first thing Kirei would do when he returned to the church was find Gilgamesh, who was more often than not waiting for him in his original form. The longer they were apart, the harder they would fuck. Kirei found new and unusual ways to find joy in their time together. No matter how much Gilgamesh screamed in pain and torment, the Servant always enjoyed their meetings. 

 

However, sometimes it was quiet. Sometimes there would be nothing going on. Kirei would stay in Fuyuki and run the church. He would still fuck Gilgamesh from time to time but it wasn’t with the same fervor. The Archer found himself growing bored. 

 

While Gilgamesh had continued to push Kirei’s boundaries, there were still plenty that he had yet to try. He was often content to let Kirei explore his own perversions. As long as it was interesting, Gilgamesh saw no problem in it. But lately, it had not been interesting. The servant thought it time to try something new. 

 

Gilgamesh found Kirei in the church, returning stray hymnals to where they belonged in the pews. Mass was over for the day, and the church was quiet. 

 

“I want to fuck you,” Gilgamesh told his Master without pretense.

 

Kirei didn’t look up. “Was yesterday unsatisfying?” he asked mildly. 

 

“You misunderstand,” Gilgamesh smirked. “ _ I  _ want to fuck  _ you _ .”

 

Now Kirei paused and met the Servant’s gaze. He frowned and set the last hymnal down. “No,” he said firmly.

 

Gilgamesh stalked forward. “It wasn’t a question.”

 

Kirei glared and turned to walk back to his quarters. “And yet I’ve answered it,” he said over his shoulder. 

 

Gilgamesh quickly caught up to the priest. He grabbed Kirei by the arm and forced his back against the nearest wall. “You’re beginning to bore me,” Gilgamesh explained. “If you could keep me entertained, I would let you dominate me as long as you wished. But our time together has become too routine and if you cannot take the initiative to fix that, then I shall.”

 

Kirei tried to pull his arm away, but Gilgamesh’s grip was firm. “This is foolish,” he told his Servant sternly. “Release me.”

 

“Maybe you’ll enjoy it,” Gilgamesh offered. “I do.”

 

“No,” the priest said again. 

 

“You can make this easier,” Gilgamesh said, beginning to sound threatening. He tightened his grip on Kirei’s arm. 

 

Kirei felt uneasy. His Servant was stubborn. He knew that Archer would do what it took to get what he wanted. It was a useful quality in a Servant, but rather inconvenient when you were the one that stood in his way. 

 

Kirei raised an arm to push Gilgamesh off of him, but Gilgamesh just grabbed that arm too. He took both of the priest’s forearms and held them in place above his head. Gilgamesh leaned in close to Kirei’s face. 

 

“Relax,” he said in voice that was far from reassuring. “It will only be worse if you struggle.”

 

Kirei struggled to pull his arms from Gilgamesh’s grasp. “This isn’t funny, Archer.”

 

“What a shame. I’m having a great time.”

 

Kirei glared and made to kick the Servant. Gilgamesh released one of Kirei’s arm to grab his leg instead. Kirei made quick use of his freed arm and forced a fist into the side of the Servant’s face. 

 

Gilgamesh raised a hand to his face, letting go of Kirei’s leg. Kieri took advantage of Gilgamesh’s distraction and wrenched his arm from the Servant’s grasp. He took a fistful of Gilgamesh’s hair and tugged the Servant’s head back. Gilgamesh hissed in pain. 

 

“Don’t underestimate me,” Kirei growled. He released the Servant.

 

Gilgamesh grabbed his Master’s face with both hands and forced their lips together. Kirei lifted a hand to rest on Gilgamesh’s chest, but didn’t push him away. He let the Archer kiss him. He felt himself being drawn in, moving his lips against the Servant’s. He was just deciding what he might like to do to punish Gilgamesh, when he felt chains wind around his legs and up his body.

 

“Archer!” Kirei yelled as the Chains of Heaven pulled his arms out to the sides. Gilgamesh smirked but kept kissing him. He slid his hands up under Kirei’s shirt, and the priest flinched away from the cold touch. He let his fingers ghost over the man’s nipples before pulling them back. 

 

“Don’t worry, I’ll be nice,” Gilgamesh said, smiling as undid the priest’s belt. “If I make your first time too bad, you’ll never want to do it again.”

 

Kirei glared at him as if to say  _ I don’t want to do it  _ **_now_ ** . He tugged in vain at the chains which now held him against the wall with his arms strung up uselessly above his head. They had moved from his lower body to allow Gilgamesh to pull his pants and underwear down to his ankles. 

 

“You’re welcome to try to fight back,” Gilgamesh told him, pulling off his Master’s shoes, “But if you do, I have no problem leaving you chained here like this for someone to find you.”

 

Kirei frowned down at the Servant. “Just get it over with.”

 

Gilgamesh straightened up, having completely removed everything from Kirei’s lower half. 

 

“Don’t be like that,” Gilgamesh said, letting his hands rest on Kirei’s hips. “Why are you so sure this won’t bring you joy?”

 

Kirei said nothing. In truth, he had thought about this many times since Gilgamesh had threatened him with it the first time they had fucked. What would it be like? Would it be painful? Humiliating? Gilgamesh got off on it, though. He seemed to enjoy being fucked. Could Kirei enjoy it too?

 

But letting Gilgamesh inside of him would mean letting the Servant have control over him. Taking him into his mouth was bad enough, but he had learned how to use that to his advantage. When it was his choice, he could use his tongue and maybe even his teeth to make his Servant swear and cry out. He would be pliant before Kirei, easily moldable into anything he wanted. 

 

But there was no skill in being taken like he took Gilgamesh. What could he do besides lie there and be violated? He could try to fight back, but Gilgamesh might be true to his word and leave him, indecent, to be found by some parishioner. 

 

Kirei was pulled back to the current situation when he heard the sound of a cork being pulled from a bottle. He looked up to see Gilgamesh pouring something over fingers. Oil? He must have pulled it from the Gate of Babylon. Unless he kept it on his person, which was not unbelievable. 

 

“Ready?” Gilgamesh asked and waited a moment, as if he would stop if Kirei said he wasn’t. The priest just tightened his jaw and readied himself for the inevitable. Gilgamesh reached between his legs and circled his finger around his entrance. The oil was warm but the sensation still gave Kirei goosebumps. Slowly, Gilgamesh slid one finger inside him. 

 

The Servant watched Kirei’s face, eagerly awaiting some kind of reaction. Kirei’s jaw was clenched, refusing to let anything show in his expression. It felt strange. Not painful, but also not something he would seek out. 

 

The finger moved in and out of him. Then a second finger joined the first. Kirei breathed deeply through his nose. It wasn’t too bad. He just felt a stretching sensation. Gilgamesh’s other hand lay on the priest’s hip, thumb rubbing up and down on the skin there.  

 

“How does it feel?” the Archer asked. Kirei said nothing. The two fingers inside him were spreading, opening him up even more. He felt his body clench at the intrusion. 

 

“Come now,” Gilgamesh said, “I’m trying to be kind. If you’re too tight, it will only hurt more.”

 

Kirei forced his gaze from his Servant and instead stared firmly at the wall across from him. He tried to let his body relax. He knew the Archer wasn’t really being kind, but he believed that it might be more painful if he didn’t do what he was told. 

 

“I can make it good for you,” Gilgamesh offered. “Help you relax.” He slid another finger inside the priest.

 

Kirei gave in and screwed his eyes tight shut. That certainly wasn’t helping. The fingers felt so wrong inside of him. He could feel them moving around, pressing against his inner walls. Gilgamesh was pawing around inside him like he was looking for something. As if-

 

Kirei’s eyes flew open. “God!”

 

Gilgamesh smirked. “It’s almost as if no one had ever touched your prostate before,” the Servant teased him.

 

Kirei felt his eyes drawn back to the Archer. A spark of pleasure had shot up his spine. It had driven all thoughts of discomfort from his mind. Coming down from the feeling, though, Kirei felt shame creep into his stomach. He didn’t  _ want _ to enjoy this. 

 

“Are you almost done?” Kirei asked, trying to sound composed.

 

“Don’t be like that,” Gilgamesh told him. “Your enjoyment is important to this. I want you to see if this brings you joy.”

 

Nevertheless, Gilgamesh withdrew his fingers. Of course, Kirei knew better than to be relieved. He looked down to see Gilgamesh pull himself from his pants. His Servant was already hard. He must have gotten off to seeing the priest squirm.

 

“This is the fun part,” Gilgamesh said, applying the oil liberally to himself. Kirei snorted. For Gilgamesh maybe, but certainly not for him.

 

The Archer lifted one of Kirei’s legs and wrapped it around his waist, drawing their hips closer together. With the hand not supporting the priest’s leg, Gilgamesh lined himself up with Kirei’s entrance. 

 

Slowly, tortuously, Gilgamesh pushed inside him.

 

It hurt. It wasn’t the worst pain Kirei had ever experienced in his life, but it still fucking hurt. He couldn’t help grunting as his Servant penetrated him. 

 

“God, Kirei, you’re so fucking tight,” Gilgamesh groaned. His now free hand slid up Kirei’s abdomen. The priest tried to squirm away from the touch, but in moving, he pushed the Archer further inside of him. Kirei gasped.

 

“If you wanted me to go faster, you could have asked,” Gilgamesh laughed. Kirei glared, but didn’t trust his voice not to shake, so he said nothing. 

 

When Gilgamesh had forced himself fully inside, he paused. The hand on the priest’s stomach was sliding up and down, smearing the skin there with oil. 

 

As much as Kirei was appreciating the reprieve from his assault, he would rather they get the whole thing over quickly. He took another moment to steady himself before speaking.

 

“I haven’t got all day,” the priest said, trying to sound unaffected.

 

Gilgamesh smirked. He loved any chance to tear down Kirei’s facade and force him to see his true self.

 

“Of course not,” the Archer said, still smiling. “Your time is important. We can speed this up.”

 

Without any more warning, he pulled out and slammed back into Kirei. 

 

Kirei cried out and threw his head back, slamming it into the wall behind him. The priest felt tears well up in his eyes at the pain in his head and ass. God, he felt so pathetic. He could handle being assaulted, why was being raped so different? He was practically crying. 

 

It wasn’t just the pain. Of course, he was in a lot of pain, but it was also his pride. He felt totally out of control. Sex was usually a power trip for him. Manipulating his Servant into giving his whatever pleasure he sought. He got off on the pain and suffering of others. Now he was the one suffering, in pain. 

 

Gilgamesh, after the initial thrust, had slowed to a more gentle rhythm. He watched, enrapt, as Kirei grunted and squirmed and bit at his lip. 

 

“You’re so beautiful like this,” he groaned as he pushed into the priest. His free hand had moved to his Master’s face, softly stroking his cheek. “I wish you could see yourself right now, Kirei.”

 

“Just,” Kirei gasped. “Just stop talking and finish.”

 

“Don’t be like that,” Gilgamesh hummed, leaning forward to kiss at the priest’s neck. He scraped his teeth along the sensitive flesh there. Kirei’s breathing quickened. “This is for you too. I want to make sure you have a good time.”

 

Gilgamesh brought his hand down between them and wrapped it around Kirei’s cock. It wasn’t hard but also not entirely uninterested. It didn’t take more than a few strokes before it grew full and heavy in his hand.

 

Kirei’s eyes were screwed shut tightly and his mouth forced into a thing straight line. He jaw ached from how hard he clenched it. His Servant’s hand felt good. Even the pain in his ass couldn’t mask that. It was torture, being forced to get off to something like this. 

 

“Is it good?” Gilgamesh teased, picking up the pace with both his hand and thrusting. “Come on, Kirei, talk to me. I want you to feel good.”

 

“St-stop talking,” Kirei gasped at him Servant, eyes fluttering open to glare at him. “Fuck me if you, ah, want, but don’t make me, mm, listen to you talk all day.”

 

“So good then,” Gilgamesh laughed, surging forward to press their lips together.

 

Kirei tried to pull away but had nowhere to go. His servant bit at his lip and, when Kirei gasped in pain, forced his tongue into the priest’s mouth.  

 

Kirei tried to focus on his breathing and ignore the assault on his ass and mouth. It didn’t help that Gilgamesh was still jerking him off and he could feel pleasure pooling in his stomach. Then one of Gilgamesh’s thrusts hit that spot inside of him (his prostate, Gilgamesh had said) and Kirei’s vision went white.

 

“Fuck, Gilgamesh!” the priest cried, forcing his face up, away from the Archer’s. In that moment, Kirei felt a sense of clarity. He looked back down at his Servant. Gilgamesh was staring back at him. The Servant’s eyes were dark and hazy. He was panting, a bit of saliva dripping down his chin. He looked wrecked. He was beautiful, Kirei realized. Just as beautiful as when he had the Servant choking on his dick or bent over a desk.

 

“Harder,” Kirei commanded. Suddenly, he didn’t feel powerless. Just because Gilgamesh was inside him, didn’t mean that Kirei couldn’t be in control. He pulled his Servant in with the leg wrapped around his waist. “Now.”

 

Gilgamesh smiled. Finally. “Of course, Father,” he purred, and slammed back into the priest. 

 

Kirei groaned. He drank in every sensation, the hand on his cock, the fullness inside him. He drank in the moans spilling from his Servant’s lips, the gasps and hitches of his breath. 

 

At some point, Kirei realized the chains had disappeared from his arms. He brought his newly freed hands to his Servant’s head, tangling his fingers in Gilgamesh’s hair. He forced their faces closer, crashing his lips onto the Archer’s. 

 

Even when they drew apart from the kiss (if you could call it a kiss), Kirei’s mouth stayed close, breathing the servant in. 

 

“I’m so close,” Gilgamesh groaned. “Fuck, Kirei.” 

 

The Servant’s movements were getting more frantic. His thrusts were quickening, his grip on Kirei’s cock tightening. Kirei could feel his orgasm drawing closer as well. What finally brought him over the edge was feeling of power he got watching his Servant gasping helplessly as he drove into him. 

 

Kirei pulled Gilgamesh’s head back by his hair and bit down hard on his neck as he came.

 

Gilgamesh cried out as Kirei’s teeth sank into his flesh. He felt the priest’s cum spilling over his fingers. Kirei rode out his orgasm, clenching around Gilgamesh’s cock. The Servant was almost at his limit.

 

When Kirei had come down from his orgasm, he looked into his Servant’s eyes. Gilgamesh looked desperate and wild. Kirei smiled. 

 

“Cum for me.”

 

And Gilgamesh did. He came much more loudly than Kirei, gasping and crying out. He thrust, weakly, a few more time before bottoming out and cumming inside the priest. 

 

Finally, Gilgamesh pulled himself from Kirei and eased the priest’s leg back to the ground.

 

“So, how was it?” Gilgamesh asked, grinning devilishly as Kirei reach down to pull his pants back up. The priest buttoned the trousers and pulled his shirt back down. He straightened his clothing and, when he felt presentable, answered his Servant.

 

“Enlightening.”

 

They both smiled at each other, as if they shared a secret only they knew. Only they understood what was going on. No one else could comprehend this. Kirei felt, in that moment, totally joyful.

**Notes for the Chapter:**

> After this, I want to add some kind of epilogue, but that'll probably be the end of this story. If I get inspired or there's interest, I might add more, but it would probably be another fic altogether.


	4. Amen

**Notes for the Chapter:**

> This is more of an epilogue than a last chapter, but it is still "SO SPICY FOR 6PM AA" according to the friend I had read it.

Life went on.

 

Kirei found himself changed in an insignificant and life altering way. He still felt the need for suffering, control, power. But he realized those things were so much more complicated than he had first thought.

 

This realization was affecting his life in many ways, but most clearly in his relationship with his Servant. He could see it play out in his mind.

 

That day, and it could have been any day, he and Gilgamesh found themselves in Kirei’s room. Maybe it was a warm summer day, maybe they were snowed in. They had just reunited or they had been there for hours. It didn’t matter.

 

Kirei was straddling Gilgamesh’s lap, his Servant laid before him. The priest held a pure white candle in his hand. It was tilting so that small drops of wax fell and burnt the other man’s chest. Gilgamesh’s head was thrown back, his arms tied above him to the head of the bed.

 

“ _ Please, Father _ ,” the Servant moaned.

 

Kirei smirked down at him. Well, since he asked so nicely.

 

Kirei blew out the candle and let it fall next to the Archer. He ran his hands up Gilgamesh’s chest, reveling in the feeling of the wax cooling on his Servant’s skin. He felt more than heard the man hiss in pain. One hand made its way to Gilgamesh’s lips, pushed fingers into his open mouth.

 

Gilgamesh immediately closed his lips around the digits and sucked in earnest. The fingers pressed down on his tongue, pushing further down his throat. He tried and failed not to gag on them. Kirei laughed as saliva spilled down his hand and onto the bed sheet below them. 

 

The priest withdrew his fingers and instead slipped his hand down between his own legs. He pressed one of his spit slick fingers against his hole and slid it slowly inside. He continued fingering himself, adding a second finger, then a third. Gilgamesh watched him, enraptured, his breathing harsh and unsteady. 

 

Kirei felt himself laugh again. At the look on his Servants face, the desperation there. At the control he had over the man. At the power he held in the fingers he was currently sliding in and out of his ass.

 

When the priest felt thoroughly prepared (and Gilgamesh looked as if he could take no more), he removed his fingers. Kirei reached over to grab a bottle of lubricant. He squeezed a small amount into his hand and rubbed it on his Servant’s straining erection. It would have been fun to make the Archer cough and splutter again as he forced more fingers down his throat, but Kirei knew from experience that saliva was not always enough.

 

Kirei knelt up above Gilgamesh, his Servant’s dick in his hand, lined up against the curve of his ass. He lowered himself slowly, impaling himself on the Archer’s cock.

 

“Fuck, Kirei,” Gilgamesh gasped.

 

“Hmm,” Kirei hummed. “I thought you had forgotten how to speak.”

 

Gilgamesh opened his mouth to respond but Kirei suddenly dug his fingernails into his Servant’s flesh and the Archer moaned instead. The priest felt the other man twitch inside of him. 

 

“You’re impossible,” Gilgamesh panted. Kirei smirked. He raised himself up and slammed back down onto the Archer. Gilgamesh moaned.

 

Kirei continued riding Gilgamesh. He watched as the Servant writhed around and tugged at his bondage. It was only rope that Gilgamesh could easily have broken free of but he didn’t. The fact the he could control his Servant without command seals, without even real shackles, was exhilarating. 

 

This was Kirei’s life. He let the beauty of it wash over him. He could feel his Servant bucking his hips up into him, feel the way Gilgamesh moaned and his breath hitched, feel the need and want and desperation. 

 

This was control. This was power. 

 

This was true joy.

**Notes for the Chapter:**

> We've finally reached the end of this wild ride. I haven't published a multichapter fic since middle school, so this has been interesting. I hope you've enjoyed it!
> 
> I've opened up my art blog to include my fics, so if you wanna reach me I'll be over on tumblr as witchofobscenity.

**Author's Note:**

> I'm thinking this'll have three or four parts. I'll try to get it out as soon as I can, but no promises.


End file.
